anaerobic infection

7/30/2019 Anaerobic Infection

1/23

ANAEROBIC INFECTION

In peacetime anaerobic infection occurs

comparatively seldom (in contaminated,

crushed, gunshot wounds, after abdominal

surgery)

in wartime it is the most common cause of

death of wounded people


2/23

ANAEROBIC INFECTION

clostridial infection

non-clostridial infection


3/23

ANAEROBIC CLOSTRIDIAL INFECTION

upon contamination with soil or in

gunshot wounds

1. Clostridium perfriges (44-50%)2. Clostridium oedematies (15-50%)

3. Clostridium septicum (10-30%)

4. Clostridium histolyticus (2-6%)


4/23


Cl. perfriges - gas formation

l. odtisedema

Cl. hystolyticus - tissue necrosis


5/23


the main local factors favoring anaerobic

infection in a wound1. a great amount of necrotized, poorly oxygenated

tissues

2. vast injury of muscles and bones3. a deep wound canal

4. the presence of a wound cavity without

connection to outer environment5. tissue ischemia due to injury of great vessels

or a tourniquet applied for a long time


6/23

The nature of local tissue change

massive production of microbial toxins(hemolysines, myotoxins and neurotoxins)

progressive tissue necrosis around wound

canal progressive necrosis of muscular tissue

quickly progressing edema

gas formation


7/23

Clinical presentationswith predominant affection of muscles

(clostridial myositis)the so-called

classic type

with predominant affection of

subcutaneous fat (clostridial cellulitis)

mixed type when all types of soft tissuesare similarly involved


8/23

Clinical presentations

According to the speed of clinical

presentations

1. fulminate2. quickly progressing

3. slowly progressing


9/23

Local signs characteristic appearance of the wound

1. lifeless appearance

2. The discharge is scanty, mucous, withunpleasant smell

3. skin around the wound is cyanotic, cold to thetouch and pale

4. bronzed or bluish spots

5. affected muscles have the appearance of boiled

meat6. musclesare edematous, of grey-brown colour;

they bulge forth from the wound


10/23

Local signs Around the wound there is a pronounced

edema that quickly spreads in the

proximal direction. The whole part of the

extremity and sometimes all of theextremity is enlarged.

Melnikovs sign - a thread tied around the

extremity becomes too tight in 20-30minutes).


11/23

Local signs

Gas formation can be pronounced to

a varying degree

1. crepitation2. blade sign

3. spatula sign

4. champagne cork sign


12/23

Local signs

X-ray examination can be valuable fordiagnostic purposes

Crauses sign (light spots due to

accumulation of gas which stratifies

muscles and separate muscular bands)

To confirm the diagnosis bacteriologicalinvestigation is used (wound smears).


13/23

General signs

Severe intoxication (weakness, thirst, nausea,

vomiting, poor sleep, retardation; sometimes

delirium is noted )

skin pallor sometimes with icteric coloration,

pinched features, dry coated tongue

Arterial pressure is often low

The pulse rate is quick


14/23

General signs

The temperature is mostly subfebrile but it

may be quite high

Blood investigation detects progressiveanemia

High leucocytosis with deviation of the

differential count to the left is typical

Diuresis is usually decreased in spite of

abundant drinking


15/23

Surgical treatment

In anaerobic infection surgery should be

performed immediately upon confirmation

of the diagnosis as a delay of 1-2 days oreven several hours considerably reduces

the patients chance of survival.


16/23

Surgical treatment

stripe incision made longitudinallythrough the whole affected area of theextremity (from 2 to 5-6 such incisions

are usually made according to thespread of lesion )

wide necrectomy, excision of the

affected area amputation and exarticulation of an

extremity


17/23

Surgical treatmentAmputation in anaerobic gangrene is

absolutely indicated upon

1. injury of a great vessel

2. a grave gunshot fracture with massivedamage of the bone

3. total gangrenous lesion of the whole

portion of extremity4. unsuccessful outcome of previous

sparing surgery


18/23

General treatment

hyperbaric oxygenation is a highlyeffective method of treating anaerobic

infection (pressure chamber with a

pressure of 2.5-3 atmospheres)

combination of antigas gangrene sera

(150 000 units of activity of polyvalent

antigas gangrene serum )


19/23

General treatment

Nonspecific treatment includes the followingmeasures:

1. blood, plasma and blood substitutes

transfusion up to 4 litres a day generalantibacterial therapy

2. general antibacterial therapy

3. rest, high-caloric nutrition

4. correction of vital functions


20/23

PREVENTION

Early radical surgical treatment of

wounds opening wide the wound

canal and with utmost excision ofunviable tissue which present a

substrate for massive reproduction

of pathogenic anaerobes


21/23

PREVENTION

Surgical treatment of most

contaminated, crushed and gunshot

wounds should not end in placing aprimary suture (except when indicated)


22/23

PREVENTION

Adequate transport and therapeutic

immobilization, use of hemostatic

tourniquet only if indicated, preventionof cooling and freezing of injured

extremityall these are important for

prevention of anaerobic gangrene


23/23

PREVENTION

If anaerobic infection is detectedepidemiological measures are

obligatory: hospitalization in aseparate ward, dressing in a separate

dressing-room, careful cleaning of

the dressing room

anaerobic infection

Documents